Concept:Sources of public opinion are the channels through which the views and attitudes of the general public are expressed, measured, or communicated.
Explanation:Opinion polls are a direct method of measuring public opinion by sampling people's views.
Social media provides a platform where members of the public openly share and discuss their opinions.
Political parties gather and represent the interests and opinions of their supporters and the wider public.
Academic journals, however, are scholarly publications that contain research and expert analysis rather than the direct, everyday opinions of the general public.
Therefore, they are not considered a primary source of public opinion.
Answer:B. Academic Journals